Utilize bitshifts correctly in signals-mach.c when storing/reading the previous GC state #53868
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…e previous GC state
vtjnash
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Mar 26, 2024
Keno
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Mar 26, 2024
src/signals-mach.c
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| @@ -54,7 +54,7 @@ void jl_safepoint_resume_thread_mach(jl_ptls_t ptls2, int16_t tid2) | |||
| for (size_t i = 0; i < suspended_threads.len; i++) { | |||
| uintptr_t item = (uintptr_t)suspended_threads.items[i]; | |||
| int16_t tid = (int16_t)item; | |||
| int8_t gc_state = (int8_t)(item >> 8); | |||
| int8_t gc_state = (int8_t)(item >> 16); | |||
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Let's do a toplevel #define for this and while we're at it, spell it 8*sizeof(int16_t).
Keno
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…e previous GC state
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Keno
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Mar 28, 2024
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I have not succeed in writing a test for this, but this was found on a CI hang together with @Keno and @vtjnash.
In essence if we hit a safepoint while GC_SAFE things can go wrong
